The drug N-benzoyl-staurosporine is used as an anti-tumour agent. In general, the preparation of N-benzoyl-staurosporine is known in the art. However, it is also known that different polymorphic forms of the same drug may have substantial differences in certain pharmaceutically important properties. Therefore, there is a continuing need for new solid forms of N-benzoyl-staurosporine and new methods of preparation.